Process of treating hydrocarbon oils



June 16, 1931. J. c. BLACK ET AL PROCESS OF TREATING HYDSROCARBON OILS Filed Jan. 51 i928 Mehari/'14%.

A O NE Patented June `16 WSE.

Lauwe OFFICE JOHN C. BLACK, OIF LOS ANGELES, AND MARVIN lPROCESS 0F TREATING- HYDROCARBON OILS,

l VApplication led January 31, 1928.* Serial No. 250,864.

in the petroleum oil at relatively low temperatures and under suiiicient pressure toretain the liquefied Ahydrocarbon gases dis'- solved in the petroleum oil ina liquid state, to remove therefrom unstable and sulphur bearing hydrocarbons without any substan- 20 tial polymerization or removal of the stable unsaturated hydrocarbons, and to produce a hydrocarbon oil which willbe stable without change of, color or further polymerization when 'stored in tanks or other containers for a period of time.

`By well-known methods, tion of naphtha or -gasoline made by thermo cracking operations, much diiculty has been found in. stabilizing the stock produced, Without a considerable loss of the stable unsaturated hydrocarbons due to polymerization and extraction, in which sulphuric acid, caustic soda, and various oxidizing agents are usually employed. By these former vWellknown methodsthe sulphuric acid employed not only extracts the yunstable hydrocarbons, but also polymerizes and extracts relativ-ely high percentages of the stable unsaturated hydrocarbons which if conserved would Vbe serviceable and useable for motor fuel.'

By our invention these difficulties are overcome and a purified stable gasoline or naphtha stock is produced without any substantial loss of the stable unsaturated hydrocar- 5 this treatment with sulphuric acid at' low in the purifica# lective in the bons by the employment of a sulphuric acid temperature in the presence of dissolved liquefied hydrocarbon gases the chemical action is modified and a selective action obtained, in which the sulphuric acid reacts substantially only with the unstable unsaturated hydrocarbons and sulphur bearing hydrocarbons with the formation of sulpho-acid or sludge, lwihch is separated from the treated gasoline or naphtha, and then finished by methods well-known in the art.

a purification y of gasoline or naphtha stock derived from.

the cracking of hydrocarbon oils, with Asulphuric acid, at low temperatures and-in the presence of liquefied hydrocarbon gases such as propane,butane, pentane, propylene, butylene, amylene and the like, Ior

other-hydrocarbon gases whichmay be derived from the gases produced in the crack- 1ng of hydrocarbon oils which are liquefiable rlatlvely low temperatures and relatively g for obtaining low temperatures of the gasolme or'na'phtha stock to be treated by vaporization of a par-t thereof.

. Another object of. this invention is to purify gasoline or n'aphtha derived from the cracking of hydrocarbon oils with a minimum loss ofthe gasoline stock.

. Another objectof' this invention is to-sepy arate low boiling gasoline stock from the gases produced in cracking hydrocarbon oil.

We are aware that it is well-known in the art to treat hydrocarbon oils at low ltemperatures with sulphuric acid, such methods being carriedout by the employment of heat exchanger systems employing ammonia or other known refrigerating agents. Such methods, however, are not as eflicient or sephur bearing hydrocarbons as are obtained by our invention.

pressures, and which may be utilized separation of unstable and sul- L. CHAPPELLVOF WATSON, CALIFORNIA v do l An object of this invention is to accomplish Our invention 'consists in an improved i method of treating gasoline or naphtha stock with sulphuric acid at low temperatures ro# duced by internal cooling in which the re rigerating a gent .is -employed directly in contact with the stock to be treated and alsov actsas a diluent to modify the reaction to the de- 'I 'y sired extent.

-methylene, pentamethylene, and the like.

In the operation of our invention, these gases are liquefied and separated from the methane gas and other gases which are not liqueliable at the temperature and pressure employed, as they come directly from the absorption tower of a cracking system by compression at pressures ranging from 100 to 300 pounds per square inch gauge and at a temperature of approximately 60 degrees F., maintained by means of a cooling and compression system of any of the, Well-known types. These liqueed Vgases are mixed with the gasoline stock to be treated in quantities sufiicient to dilute the gasoline to the desired degree. The treatment of the diluted gasoline is preferably carried out at a temperature of approximately 17 degrees F. andthe quantity of sulphuric acid employed may range from as low as 1 pound to as high as 40 pounds per barrel of gasoline stock, the amount employed depending upon the stock treated and the products desired.

Various further objectsand advantages of the present invent-ion will be understood from a description of a preferred process of treat ing hydrocarbon oils containing dissolved liquefied hydrocarbon gases with snlphuric acid at low temperatures. For this purpose, there is hereafter set forth a specific example of one form ofv process which embodies the invention. The process is described as it is Vcarried out in the apparatus illustrated in the Iaccompanying drawing.

The drawing represents a diagrammatical view of an apparatus forcarrying out the invention. i

Referring to the drawing, 1 indicates a pipe for conveying the gasoline or naphtha stock to be treated, froln a source not shown, through a cooler or pipe heatexchanger coil 2, contained -in the tank 3. 4 indicates a gauge glass connected to tank 3 for observing the oil level in the tank 3. 5 indicates a pipe or continuation of cooler coil pipe 2, -which conveys the cooled oil to be treated into the bottom of treating tank 6.l 7 indicates agauge glass connected to the treating tank 6 for observing the sludge level 55. 56 indicates a distributor plate so that the incoming gasoline stock may be uniformly distributed as it passes up through the treating tank 6. 8 is a pipe connected to the top of treating tank 6 and conducts the oil for further treatment into the bottom of treating tank 9, which in like manner is provided with a distributor plate 10. the acid sludge level being indicated bv the number 13. The sludge level in treating tank 9 is observed by means of the gauge glass 12 which is connected to said treating tank 9. 11 indicates a distributor plate in the top of treating tank9, by means of which the sulphuric acid' introduced is even-1y distributed as it passes downward through the gasoline stock in the said treating'tank9; 16 is an acid tank whichis filled with sulphuric acid of the desired strength through the pipe 18'Which leads to a source not shown, and controlled by the valve 19. 17 is a gauge glass by means of which the level of the acid contained in said acid tank 16 may be observed. Connected to the bottom of acid tank 16 is a pipe 14 controlled by a valve 15, which is connected to the treating tank 9. 20 is a pipe connected to the top of treating tank 9 which conveys the treated cold oil into the exchanger tank 3. The exchanger 3 is provided with a dome atA the top to which is connected a Apipel 34 controlled by a valve 35. The pipe 34 is connected to the pipe 36 and leads to the suction side of compressor 38. 23 is a tank provided with a steam heating coil 24 controlled by Avalves 26 and 28,\the pipe 25 leading to a source ofsteam not'shown, and the-pipe 27 leading to a steam trap not shown. The tank 23 is provided with a gauge glassl 29 by means of which the level of the treated oilmay be observed. The pipe 2l controlled by valve 22 connects the exchanger tank 3 to the tank 23 at the top, by means of which treated oil after cooling the incomingV oil overflows intoA the said tank 23 where it is heated and most of the lower boiling hydrocarbons are expelled from the treated gasoline stock and then compressed to aliquid by the compressor 38 which takes suction on the top of said tank 23 through a dome as shown. Heater tank 23 is provided with an outlet pipe 31 controlled by a valve 30 which conducts` the treated oil to a storagenot shown. The pipe 32 is connected to the top of heater tank 23 and leads-to the suction side of the compressor 38 controlled by the valve 33. 39 is a pipe connected to the discharge side of compressor 38. The pipe 39 is connected to the condenser coil 40 which is a prolongation of the pipe 39 in the condenser box 41, from where the liquefied hydrocarbon gases are conducted through a pipe 42 which is connected to a storage tank 46. The tank 46 is provided with a gauge glass 43, by means of which the level of the liquefied hydrocarbon gases may be observed. 44 is a pipe/ which is connected to the tank 46 at the top-controlled by a valve 45 and leading to a source of liquefied hydrocarbon gases not shown. 36 is a pipe which connects the tank 46 at the top, controlled by a valve 37 which'leadsto the suction side of a compressor 38. 47 is a pipe controlled by valve 48 which connects the bottom of the tank 46 to pipe by means of which the requiredl I quantity of liquefied hydrocarbon gases may nected at the top bythe pipe be introduced into the flow of gasoline stock coming through vthe said pipe 5. The pipe 49 connects atreating tank 6 at the bottom to an acid sludge tank 51 controlled by av valve 50.

- controlled by valve 54, connecting treating i well-known.

tank 9 With treating tank 6. The pipe 61 controlled by the valve 60 represents a line for conducting the sludge to apparatus noty shown for recovery of the acid by methods The preferred process as carried out with i Athe; apparatus thus described as as follows:

- outgoingtre'ated oil,

rea ents 25g g 1 Petroleum oil orpetroleum oil distillate, such as gasoline stock made by any of the Well-known cracking operations which has treatment Withpreferably had a preliminary caustic soda, sodium-hypochlorite or similar for the removal of hydrogen sulphide and mercaptans therefrom', is conducted from pipe 1 through cooler or exchanger coil 2 into the bottom-ot treating tank 6, passing through pipe 5 which is a prolongation of the heat exchanger coil 2. Heat exchanger coil 2 issurrounded by the which is maintained at F., by taking sucapproximately 17 degrees the pipe 34 which tion on the tank 3 through leads to the suction side ot acompressor 38,

controlled by valve 35.

lower boiling liquefied hydrocarbon. gases contained in the treated oil changes -to a gas, thereby cooling the treated gasoline stock containing the liquefied hydrocarbonl gases t0 .a low temperature, by means ofvvhich the petreating tank 6 along with a regulated low desired degree.l

,l fied hydrocarbonl which is accomplished by opening the valve. 37. which admits the hydrocarbon gases into of liquefied Vhydrocarbon gases comingfrom tank 46 throughthe pipe 47 controlled by valvej48, rllhe liquefied hydrocarbonl gases,l at the rate of approximately 10 to 20per cent by volume ofthe gasoline stock, 'which are to be treated, arelmain means of evaporating a portion of the liquethe suction side of compressor 38 thereby cooling the liquefied hydrocarbon gases to the containing the required quantityof liquefied hydrocarbon gases at the-required tem-- perature passes into the treating' tank Gand up through a distributor plate 56y which is plate 11 so that the same or partial removal incoming gasoline By means o'f this said suction taken on the tank 3, a portion of thegases containedA in tank 46,

rlhe. petroleum. Vdistillate provided With openings so that the gasoline stock containing the liquefied. hydrocarbon same time, sulphuric acid in the desired quantities is introduced into the top of said treating tank 9 passing through thedistributor through the oil in small droplets or s treams.

The acid treated gasoline stock passes out otl treating tank 9 through the pipe 20 and into tank 3 4Where the aforesaid heat exchange takes placa. the` acid treated coldygasolin'e stock absorbing a part of' the heat from the A i stock. ,As heretofore stated, the temperature of the treated cold'oil coming int-othe exchangertank 3 may be further cooled by evaporating a portion of the liquefied hydrocarbons by taking suction through pipe 34 -which is connected to (the tank 3 at the-top. The treated oil passes from tank 3 into the tank 23 Where the remainder ofthe liqueedhydrocarbou gases not suitable for gasoline stock are-removed by A-means of heating said gasoline stock to the required temperature' by means of the heater coil 24 and ltaking suction on said tank 23 through the pipe 3 2 which leads to the suction side of compressor38. The treated oil 1n biiingiiquened may be utilized hydrocarbon gases evolved during the operations from the tanks 3, 23, 5,1 and 46 arecomthe level of may pass downward los ly and only such quantities that are through the valve 62 pressed by the compressor 38 and then passed through the cooling coil 40 which is surrounded by a cooling medium contained in the oo ndenser box 41. By this said compression and cooling, the hydrocarbon. gases are liquefied and pass tlirough the'pipe 42 which is a prolongation of thev cooler coil- 40,. connected to thetank 46.

. The sapeur-1C acid empioyeai this Oper-j ation may be of varying strength, depending upon the stock treated and the product desired. 'In case a gasolineV stock containing a very high percentage of unsaturated hydrocases we may employfuming sulphuric acid containing 3 to as high as 1,5 per cent S03. Forexample, in the treatment of gasoline stock made by cracking a petroleum oil distillate at a. pressure of approximately 1000 pounds gauge, by our process approximately 4 to l0 pounds of 3 per cent fuming sulphuric acid per barrel of the gasoline stock was required to obtain a stable water white gasoline product with a-treating lossranging from 1 to 5 per cent by volume; while by the employment of Well-known methods of treating a loss of from 5 to as high as 8 per cent by volume was obtained, employing the same quantity of acid.

The acid sludge produced by this operation may be recovered by any of the well-known methods of hydrolysis'and the reco-vered acid employed again for this treatn'lent or for the treatment of other hydrocarbon oils.

It is tobe understood that a preliniinary treatment of the gasoline stock with caustic soda may not be necessary for gasoline stocks derived from a relatively low sulphur content crude petroleum oil.

It is also to be-understood that this treating process may be carried out intermittentlyT or in batch lots, and that the treatment of the gasoline stock containingl the requisite amount of liquefied hydrocarbon -gases may be carried out by commingling the gasoline stock With the required amount of sulphuric acid by any other preferred or suitable method.

While the process herein described is well adapted for carrying out the objects of the present'invention, it is to be understood that various `modifications and changes may be made without departing from the spirit of the invention, and t-he invention includes all such modifications and changes ascome within the` scope of the appended claims.

1. A process-of treating gasoline or naphtha with sulphuric acid in the presence of liquefied hydrocarbon gases, comprising commingling the gasoline or naphtha containing not less than 10% by volume dissolved liquefied hydrocarbon. gases at temperatures below 32 degrees F., with the requisite amount of sulphuric acid, containing not less than 76 per cent by Weight sulphuric acid and thenseparating the products of rei action and low boiling liquefied hydrocarbon. gases from the treated gasoline or naph- 2. A process of treating gasoline or naphtha withlsulphuric acid in the presence of dissolved-'liquefied hydrocarbon gases, comquantity of sulphuric acid containing not less than 7 6 .per cent by weight sulphuric acid at temperatures belon7 32 degrees F., and then separating the acid products of the reaction i and low boiling liquefied hydrocarbon gases from the treated gasoline or naphtha..

3. A process of the class described, comprising treating gasoline or naphtha containing not less than 10% by volume cooled liquefied hydrocarbon gases, with sulphuric acid containing not less than 7 6 per cent by weight sulphuric acid at temperatures below 32 degrees F., to extract therefrom unstable hydrocarbons and sulphur bearing hydrocarbons.

4. A process of the class described, comprising treating gasoline or naphtha containing not less -than 10% by volume dissolved vlower boiling liquefied hydrocarbons, with sulphuric'acid at temperatures below 32 degrees F., to extract therefrom unstable hydrocarbons and .sulphur bearing hydro-- carbons by a .-counterflow treatment in which the gasoline or naphtha reduced to the said low temperature is first commingled with lower boiling hydrocarbons and then caused to pass in counterflow contact to a sulphuric acid containing not less than 76 per cent by weight sulphuric acid reagent,

5. A continuous process of treating gason line or naphtha, comprising continuously introducing and cooling the gasoline or naph.-

tha by an exchange of heat from the treated outgoing Cool gasoline or naphtha, continuously introducing'into said flow of cooled gasolinel or naphtha, cooled lower boiling liquefied hydrocarbon gases, causing said .cooled gasoline or naphtha containing the dissolved lower boiling liquefied hydrocarbons to pass through a treating tank in counterflow to streams or droplets of sulphuric acid containing not less than 76 per cent by Weight sulphuric acid, and then separating the acid sludgefand the lower boiling hydrocarbons from thetreated gasoline or naphtha.

- 6. A process of treating gasoline or naphtha made by cracking petroleum oils, comprising continuously introducing andl cooling the gasoline or naphtha by an exchange of heat from the treatedoutgoing cooled gasoline or naphtha,continuously introducing into said flow of cooled gasoline or naphtha, cooled liquefied hydrocarbon gases derived from the ils cracking of petroleum oils, causing said cooledgasoline or naphtha containing the dissolved liquefied hydrocarbon gases to pass through a treating tank in counteriow to streams or droplets of sulphuric. acid containing not less than 7 6 per cent by weight sulphuric acid, and then separating the acid sludge and the low boiling hydrocarbons from the treated gasoline or naphtha.

7, A process of treating gasoline stock made? by cracking petroleum oil, comprising treating the gasoline stock lwith liquefied hydrocarbon gases,

remesa 8. A process of purifying gasoline'l stock made by cracking petroleum oils, comprising cent by weight below 32 degrees'l., in quantities suflicient to c treating the same with liquefied gases from ay petroleum oil cracking system'and with sulphuric acid 'containing not less than 76 per sulphuric acid' at temperatures combine with the unstable hydrocarbons and with the sulphur bearing hydrocarbons to be separated, separating 4the treated gasoline stock from the acld products of the reaction,

v and .then separating the dissolved liquefied hydrocarbon gases which are not suitable 'forl gasoline stock, trom the treated gasoline.-

9.l A continuous process of 'treating gaso line' or naphtha, comprising, passing the gasoline or naphtha in heat exchange relationship with cold gasoline or naphtha subsequently produced, continuously introducing into'the first mentioned gasoline or naphtha, cooledliquefied hydrocarbon gase's, passing said gasoline or naphtha containing at least 10 per cent by volume of the said liquefied hydrocarbon gases, in countercurrent flow -with streams of sulphuric acid containing not less than 76 per cent by weight sulphuric acid, and thenv separating the acid sludge formed and the liquefied hydrocarbon gases trom'the treated gasoline or naphtha.

10. A process of treating gasoline4 or naphtha derived -rom' cracking. 'petroleum oil,

' comprising, continuouslypassing said ga'sol'ineor naphtha in heat exchange relationship with cold 'gasoline or naphthasubsequently produced, introducing cooled liquefied hydro# 'carbon gases into said first mentioned gasoline or naphtha, passing said rst mentioned gasoline or naphtha containing at least 10 per cent by volume liquefied hydrocarbon gases in counterow with sulphuric-acid containing not less than 76 per cent by weight sulphuric acid, 'separating the acid sludge formed and thereafter separating the liquetied. hydrocarbon gases from' the treated gasoline or naphtha, by distillation;

1. A method of separating unstable, `unsaturated hydrocarbons from gasoline stock containing the same, comprising, subjecting the gasoline stock containin Vnot -less than 10 per c'ent liquefied hydrocar boiling points less than the gasoline stock to the action -o'f sulphuric acid containin not less than 76 per 'centi by weight sulp uri'c acid at temperatures below -32 degrees F,

derived fromthe cracking ot and with sulphuric acid con- "ume dissolved liquelied and lower taining not less than hydrocarbons carbons.

on gases having 12. The method of separating unstable, un-- saturated hydrocarbons from stable unsaturated hydrocarbons, without removing the latten, comprising, adding liqueiied hydrocarbon gases to the gasoline stock to be treated, commingling said gasoline stock containing at least 10 per cent by volume liquef, l

iied hydrocarbon gases with sulphurc acid containing not' less than 76 per cent by weight sul%l`1uric acid at temperatures belovs7 32 degrees separating the treated gasoline stock from the acid sludge formed and thereafter separating the liquefied hydrocarbon gases Jfrom the said treated gasoline stockby distillation.

13. In the process of acid-treating'gasoline or'naphtha containing unstable unsaturated hydrocarbons to 4tree the gasolineA or naphtha from the same, the step which comprises subjecting the gasoline or naphtha' lat temperatures below 32 degrees F. to the action'ot acid in the presence of added quantities of' liquefied hydrocarbon gases dissolved in the gasoline or naphtha." 14. A processv of treating'gasoline or naphum-ing sulphuric tha with turning sulphuric acid in the presence of liquefied hydrocarbongases, comprising, commingling the gasoline' or naphtha containing not less' than 10 per cent by volhydrocarbon gasesat temperatures below 32 degrees F. with the. requisite amount of turning sulphuricacid and then separating the products of reaction boiling 'liquefied`- hydrocarbon gases from the treated gasoline or naphth'a.v

15. A process of the class described, comprising, treating gasoline or, naphtha con- 10 per cent by volume of cooled liquefied' hydrocarbon gases, .with

'turning sulphuric acid at temperatures below to extract.` therefrom unstable 32 degrees F.,

and sulphur'bearing yhydro- 16. continuous process of treating ga so. line or naphtha, comprising, continuously 1ntroducing and cooling the gasoline or naph-` tha by an exchange'of heat from 'the treated outgoingcooled gasoline o'r naphtha/continuously introducing into said flow of cool gasoline or naphtha,-- cooled lower boiling liquetied hydrocarbon gases, 'causing said cooled gasoline or naphtha containing the dissolved lower boiling liqueiied hydrocarbons to pass through a treating streams or droplets of turning sulphuric acid and then separating' acid sludge and the lower boiling hydrocarbons from the treated gas oline or naphtha.v A 17. A process of puritying gasoline st ock made by'cra'ckingy petroleum oils,- comprising, treating the 4same with'liquefied gases from a petroleum oil cracking system and with tank in countertlow to I filming sulphuric acid at-temperatures below 32 degrees F., in quantities suiflcient tocom- 'with the sulphur bearin hydrocarbons to be separated, separating t e treated gasoline stock from the acid products of the. reaction, and then separating the dissolved liquefied 5 hydrocarbon gases which are not suitable for gasoline stock, from the'treated gasoline.

In testimony whereof We aix our signatures.

JOHN C. BLACK. MARVIN L. CHAPPELL. 

